An (un)happy nation. Are Ukrainians really the unhappiest people in Europe?

In UN’s fifth World Happiness Report published two months ago, Ukraine was ranked 132nd out of 155 countries, becoming the most unhappy European state. Are Ukrainians really so unhappy?
In the past year, Ukraine went down 9 places in the happiness ranking, reaching its historical minimum. Thus, Ukraine became the unhappiest country in Europe. Neighboring countries are ranked much higher: Russia is in the 49th place (5.963 points); Poland, 46th (5.973); Belarus, 67th (5.569); and Moldova, 55th (5.838). But are Ukrainians really so unhappy, and if so, then why? Or, was this outcome influenced by the ranking methodology?